Derivative Instruments and Hedging Activity (Details - Not designated as hedges) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 25, 2020	Sep. 25, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss)
Gain on foreign currency derivatives recorded in earnings, net	$ 400	$ 2,700
Not designated as hedging instrument \| Prepaid expenses \| Foreign currency forward contract
Derivative Instruments, Gain (Loss)
Notional amount, asset	10,517	10,517	$ 13,734
Fair value, asset	28	28	95
Not designated as hedging instrument \| Other liabilities and accrued items \| Foreign currency forward contract
Derivative Instruments, Gain (Loss)
Notional amount, liability	10,831	10,831	5,757
Fair value, liability	$ 22	$ 22	$ 16

Nominal or face amount used to calculate payments on the derivative asset.

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